Multimedia capturing capabilities have become common features in portable devices. A multimedia call between two or more attendants may comprise simultaneous transmission of both audio and video signal. On the other hand, many people tend to record or capture audio and video content in an event, such as a music concert or a sport event, they are attending.
Background noise causes challenges for audio coding and for the overall quality-of-experience in mobile multimedia communications. Multimedia terminals are often used in surroundings with high background noise levels making the multimedia capturing vulnerable to background noise. In order to improve audio quality, multimedia terminals typically apply noise suppression (a.k.a. noise cancellation) as a pre-processing step before the voice signal is subjected to audio encoding. The noise suppression can never perfectly distinguish between the voice and the background noise, and therefore, a noise suppressor is typically designed to provide a fixed trade-off between attenuating background noise as much as possible and causing as little degradation as possible for the voice signal itself.
However, a straightforward application of such fixed trade-off between these two is not optimal. For example, in some multimedia capturing it is desirable that also the ambience is conveyed as well as possible (e.g. when being in a live music concert) while in others (e.g. when trying to explain an important issue in high-noise environment) all background noise will reduce the clarity and intelligibility of voice and is hence unwanted. In other words, what should be considered as unwanted “background noise” depends on the context of the multimedia capturing session. Furthermore, a user of the multimedia terminal has no means to adjust the noise suppression or any other pre-processing to be more optimal for a particular multimedia capturing session.